Radial keratotomy for the optical rehabilitation of mild to moderate keratoconus: more than 5 years' experience.

ABSTRACT

PURPOSE: To present the authors' long-term experience of radial keratotomy (RK) for the optical rehabilitation of patients with mild to moderate keratoconus--central corneal thickness of greater than 400 microm and without apical scarring. METHODS: In this observational, noncomparative series of cases, all consecutive patients with mild or moderate keratoconus, treated by RK between 1990 and 2002, with at least 1 year follow-up were included. A total of 170 eyes of 96 patients were investigated. Mean follow-up was 42.08 +/- 28.14 months. Visual acuity, refraction, corneal curvature, central corneal thickness, and complications were evaluated. RESULTS: In all of the control visits, mean uncorrected and best spectacle corrected visual acuities were better than preoperative values (p<0.0001). Preoperative myopic spherical refraction decreased significantly (p<0.0001), and remained relatively unchanged throughout the follow-up (p=0.43). A small but statistically significant decrease from baseline was ob-served in astigmatism (p=0.038), which almost disappeared 1 year after the surgery (p=0.47). The surgery produced a statistically significant flattening of the corneal curvature (p<0.0001). Central corneal thickness did not change significantly (p>0.05) in either control visit. In 33 eyes (19.4%), re-deepening of the incisions was required. In 3 eyes (1.8%) penetrating keratoplasty was performed, due to disease progression in 2 eyes (1.2%) and acute traumatic hydrops in 1 eye (0.6%). In 4 eyes (2.2%) microperforation, in 2 eyes (1.2%) macroperforation, in 1 eye (0.6%) infectious keratitis, and in 1 eye (0.6%) hyperopic shift occurred. CONCLUSIONS: RK surgery was found to be a reasonable option for the rehabilitation of a selected group of keratoconus patients in the early or moderate stages.